Early treatment of the disease is more effective than later treatment. This means that good studies have shown that early treatment, compared with later treatment, helps patients to live longer, live healthier, or have a better quality of life.

Diagnostic workup and/or early treatment of the disease doesn't have serious harms that outweigh the benefits of screening.

The screening test is accurate, available, and acceptable to patients.

Taken altogether, the benefits of a screening test must outweigh the harms in order for a screening test to be routinely recommended.

Routine screening for peripheral arterial disease and carotid artery stenosis is not recommended because the evidence suggests that the harms of screening for these conditions outweigh the benefits.

What is the Rationale for Not Routinely Screening for Peripheral Arterial Disease (PAD)?

Asymptomatic PAD is common, and the screening test for PAD (doppler-recorded ankle-brachial index) is non-invasive and accurate. However, treatment of asymptomatic PAD, beyond standard cardiovascular risk assessment and treatment, does not improve major health outcomes. Smoking cessation and physical activity do improve maximal walking distance in men with early PAD, but these treatments should be recommended regardless of a PAD screening test result. Furthermore, screening for asymptomatic PAD in the general population leads to a significant number of false-positive results and unnecessary work-ups that may result in harms including labeling and significant adverse events associated with diagnostic evaluation (catheterization and angiography) and treatment (anti-thrombotics, angioplasty, bypass surgery). Therefore, for asymptomatic adults, the harms of routine screening for PAD exceed the benefits.

What is the Rationale for Not Routinely Screening for Carotid Artery Stenosis (CAS)?

A relatively small proportion of disabling strokes that occur without warning are caused by CAS. The most common screening test for CAS is duplex ultrasonography, which has only moderate accuracy resulting in significant numbers of false positive results. Under ideal clinical trial conditions (highly selected patients, surgeons, and hospitals), carotid endarterectomy for asymptomatic, severe CAS reduces the 5-year absolute incidence of all strokes or perioperative death by about 5%. Significant harms are associated with CAS screening, including harms associated with the angiographic work-up and complications from surgical treatment, including a 3% risk of stroke or death. Therefore, for asymptomatic adults, the harms of routine screening for CAS exceed the benefits.

How Should I Talk With Patients About These Tests?

Tests for PAD and CAS should not be routinely offered to asymptomatic adults. However, patients may ask about getting screened with these tests as a result of community health fairs, direct-to-consumer advertising, or health experiences of a friend or family member. Consider the patient's request respectfully. Discuss the patient's concerns and provide more information if needed.